It sounds like you have a networking problem since your computer can't access any internet resources. Try the following:
Click the Start button, select "Run...", type "cmd", and click "OK".
After the command prompt loads, type "ipconfig /renew" (without quotes), and press the Enter key. The program may take a few seconds or a few minutes to run. You'll know that it is done when you see a new prompt waiting for input.
At that point, right-click the top part of the window, click "Edit", click "Select All", and then repeat the last steps but click "Copy" instead. After you have copied the text in the window, paste it in your reply. Please put all the copied text inside of code tags ([code]copied text[/code]) so that I can read it.